Grate-bar



(No Model.) 2 sheets-'sheet 1.

J. T. HAMBAY. GRATE BAR.

No. 330.694. Patented Nov. 17, 1885.

WITNESSELS: INVENTOR, DMWMS'LDM 'Vga/(Me ATTORN Y.

(No Model.) I J. T. HAMBAYL 2 Sheets-Sheet 2.

@RATE BAR.

No. 330,694. Patente-d Nov. 17, 1885.

0000 OOO() INVENTOR, l OQLFJ BY Z? ATTORNEY.

a direct and a series of return air-passages, as

i UNITED STATES PATENT OEErcE.

JAMES HAMBAY, OF PITTSBURG, PENNSYLVANIA.

GRATE- BAR.

SPECIFICATION forming part of Letters Patent No. 330,694:I dated November 17,1885.

Application filed .August 13, 1885.

To all whom, t may concern.-

Be it known that 1, JAMEs T. HAMBAY, residing at Pittsburg, in the county of Al1egheny and State of Pennsylvania, a citizen of the United States, have invented or discovered certain new and useful Improvements in Grate-Bars, of which improvements the following is a specification.

In the accompanyingdrawings, which make part of this specification, Figures 1 and 2 are transverse and longitudinal sectional views of a boiler`furnace provided with my improved form of grate-bars. Figs. 3 and etare similar views showing'a modified form of grate-bars. Figs. 5 and 6 are sectional elevations of a fireplace and a stove, respectively, provided with the improved grate-bars. Fig. 7 is a top plan View of the re-place shown in Fig. 5.

The invention herein described relates to certain improvements in the construction of gratebars for furnaces, stoves, and other heaters, especially adapted for use in .connection with gaseous fuel, although they may be advantageously employed in connection with solid fuel; and the object of said invention is to proi vide a suitable supply of highly-heated air at that point where combustion occurs in the furnace, and thereby effecting a more perfect combustion without the loss of heat necessarily attendantin the use of cold air to assist in combustion; and to this end my invention consists in the construction and combination of parts, substantially in' the manner hereinafter described and claimed.

In applying my invention to heating steamboilers, the furnace of the latter is built in the usual Inanner,having the bridge-wall 2 and the flue 3 extending longitudinally under the boiler 4, as clearly shown; but in lieuof the ordinary grate-bars I substitute hollow bars 5, having a direct and a return air-passage, 6 and 7, as shown. The bottom ofthe fire-chamber may be formed of a series of independent grate-bars, each having one direct air-passage, 6, and one or more return-passages, 7, as` shown in Figs. 1 and 2; or the grate-bars of the fire-chamber may be formed in single pieces provided with shown in Figs. 3 and 4. rIhe grate-,bars shown in Figs. 1 and 2 are preferably formed of. castiron, the lower or direct air-passage, 6, open- Serial No. 174,254. (No model.)

ing at the front end of the bar into the ashpit or open space 8 under the grate-bars, and communicates at its rear end by openings 9 with the upper or return air-passages, 7 ,which open at the front end of the grate-bar into the front end of the fire-chamber 10; or, in lieu of the series of bars formed as above stated, the'bottom of the fire-chamber may be formed of a single metal plate, 11, extending from a point near the front wall ofthe ash` pit to the rear wall, completely covering the pit, with the exception of a small space or slit at the front. Over this plate 11 is placed another plate, 12, but at a distance above the plate 11,said plate 12 extending from the front wall of the furnace to its rear wall, and on this plate 12 is secured the corrugated plate 13. The alternate corrugations ofthe plate 13, in connection with the plate 12, form the return air-passages 7, which are connected to the direct air-passage 6, formed by the plates 11 and 12 by holes or openings 9 through the plate 12. rlhe corrugated plate 13 extends from the rear wall of the furnace to a point near the front wall, sufficient space being left between the front end of the plate 13 and the front wall to permit of the escape of air into the firebox. In the re-box, and immediately in front of the-open ends ofthe return air-passages,is located a burner, 14, provided with perforations or slits for the escape of gas, and connected by a pipe, 15, to any suitable source of gas-supply. The air as it passes along the direct and return passages in the grate-bars is highly heated and combines, as it escapes from the return air passages, with the ignited gas, thereby insuring a nearly perfect combustion Without any chilling effects. By increasing the number of return air-passages a more complete and thorough heating of the air is effected and a more perfect commingling with the ignited gas.

In Figs. 5, 6, and 7 I have shown my invention applied to ordinary heating-stoves and fireplaces, in which the bottom grate-bars are constructed in a manner substantially the same as that above described; but the fire-chamber of the stove or fire-place is preferably closed in by a screen, 16, as shown.

If desired, nre-bricks may be piled in open order upon the grate-bars to furnish a heating body. The admission of air is regulated by suitable dampers in the ashep'it doors, as is customary in using solid fuel.

I do lnot Wish to limit myself to the use of my improved grate-bars in connection with gaseous fuel, as they may be advantageously employed to increase the combustion of solid fuel.

If desired, the gas-burner 14 may be l0-V cated within the front end of the direct airpassage G, (see Figs. 5, 6, and 7,) in which case both the gas and air are mixed and heated before escaping from the return-passages into the fire-box, Where combustion takes place; but I prefer to arrange the gas-burner as shown in Fig. 4, as by heating the air its spe cie gravity is caused to approach more nearly to'that of the gas, and will therefore combine more readily therewith.

JAMES fr. HAMBAY.

Witnesses:

DARWIN S, WOLGOTT, FRANCIS X. BARR. 

